LOCAL MAGNETIC-PROPERTIES OF ULTRATHIN FERROMAGNETIC FCC-FE-FILMS ON CU(001)

Conversion electron Mossbayer spectroscopy (CEMS) on three monolayers (ML) thick metastable fcc-Fe(001) films grown epitaxially on a Cu(001) substrate under different conditions shows that these films are chara cterized by a distribution P(B-hf) Of magnetic hyperfine fields B-hf. The vast majority of Fe-57 nuclei experience relatively large hyperfin e fields at low temperature. The temperature dependence of the most pr obable field B-peak was found to follow a T-3/2 spin-wave law below 30 0 K. It is shown from the relative line intensities that preferential Fe spin orientation perpendicular to the film plane exists in films gr own at similar to 120 K, while preferential in-plane spin orientation is found for a growth temperature of similar to 300 K. Coating a low-t emperature grown Fe film by similar to 2 ML of Cu(001) drastically red uces the hyperfine field, in contrast to the case of room-temperature grown Cu-coated films.